This may be my favorite "Children of Time" book yet (and I really liked the first and second book).
I'd say the biggest reason I enjoy science fiction is being exposed to new ideas. In book one of this series, I enjoyed imagining how a hunter spider species would evolve when imbued with a "brainiac-empathy" gene. In book two, I loved the idea of a central (Id) mind with a 8 distributed actuators (ego).
This one introduces the notion of a punchy, aggressive, status driven mantis shrimp.
I really enjoyed thinking about what it would mean to be an evolved mantis shrimp. Human beings have technically carried around deadly weapons since we developed tools. But a mantis shrimp is an organism that has two deadly weapon everywhere it goes. Imagine how much different human society/evolution/whatever would have been if we were constantly holdings blunderbuss' at each others heads at all times? Where being in range literally meant that either party (whoever fires first) can immediately and almost certainly kill the other. I suppose we have had potentially deadly weapons since we realized we could brain with rocks, but this is a risky (and messy) way to do things compared to the instant death that a mantis shrimp represents. What would that do to trust, to boundaries, to aggression and bluffing?
It is just such a fun humorous world, where 4 (5 with lowercase humans) species are learning to coexist despite their very different ways of looking at the world.